1. Technical Field
The present disclosure relates to an electrosurgical instrument and, more particularly, to an electrosurgical instrument including a drive assembly in operable communication with an end effector to effect movement of one or both of a pair of jaw members from a spaced-apart configuration to a closed or clamping position.
2. Description of Related Art
Electrosurgical forceps are well known in the medical arts. For example, an electrosurgical endoscopic forceps is utilized in surgical procedures, e.g., laparoscopic surgical procedures, where access to tissue is accomplished through a cannula or other suitable device positioned in an opening on a patient. The endoscopic forceps, typically, includes a housing, a handle assembly including a movable handle, a drive assembly, a shaft and an end effector assembly attached to a distal end of the shaft. The end effector includes jaw members that operably communicate with the drive assembly to manipulate tissue, e.g., grasp and seal tissue. Typically, the endoscopic forceps utilizes both mechanical clamping action and electrical energy to effect hemostasis by heating the tissue and blood vessels to coagulate, cauterize, seal, cut, desiccate, and/or fulgurate tissue.
To effect movement of the jaw members, certain types of endoscopic forceps utilize a cam slot and cam pin configuration located at a distal end of the shaft adjacent the jaw members. In particular, a drive rod of the drive assembly, typically, includes a cam pin extending from a distal end thereof. The cam pin is, typically, integrally formed with the drive rod or, in certain instances, is operably coupled thereto via one or more coupling methods, e.g., soldering, brazing, welding, etc. The cam pin is operably coupled to one or more cam slots that are disposed on the jaw members. For example, in the instance where each of the jaw members is configured to rotate or move, i.e., a bilateral jaw configuration, each of the jaw members may include a respective cam slot that is configured to operably couple to the cam pin on the drive rod. Alternatively, one of the jaw members is movable with respect to the other jaw member, e.g., a unilateral jaw configuration. In this instance, one of the jaw members includes a cam slot that is configured to couple to the cam pin on the drive rod.
As can be appreciated, forming a drive rod with a cam pin and, subsequently, positioning the cam pin within the one or more cam slots on the jaw members may increase manufacturing costs of the electrosurgical endoscopic instrument and/or increase production. Moreover, and in the instance where the cam pin is not integrally formed with the drive rod, e.g., soldering is used to join the cam pin to the drive rod, there exists the likelihood of the cam pin uncoupling from the drive rod during use thereof, which, in turn, may result in the electrosurgical endoscopic device not functioning as intended. That is, one or both of the movable jaw members may not move from an open configuration to a clamping configuration or vice versa.
In addition to the foregoing, it is sometimes desirable to provide a specific closure force at the jaw members when the jaw members are in the clamping configuration. To achieve this desired closure force, one or more devices, e.g., a resilient member such as, for example, a spring, may be operably coupled to the jaw members, drive rod, handle assembly, or other device associated with the electrosurgical endoscopic instrument. As can be appreciated, having to add the resilient member to the electrosurgical endoscopic instrument may further increase manufacturing costs of the electrosurgical endoscopic instrument and/or increase production time of the electrosurgical endoscopic instrument.